Electrical apparatus



Dec. 20, 1932.

.1. w. ALLEN EIJEGTRICAL APPARATUS Filed Oct. 50, 1931 2 Sheets-Sheet 1Dec. 20, 1932. J. w. ALLEN ELECTRICAL APPARATUS Filed Oct. 30, 1951 2Sheets-Sheet 2 Patented Dec. 20, 1932 UNITED STATES PATENT OFFICE JOSEPHWILLIAM ALLEN, OF EAST ORANGE, NEW JERSEY, ASSIGNOR TO BENDTX AVIATIONCORPORATION, OF EAST ORANGE, NEW JERSEY, A CORPORATION OF DELAWAREELECTRICAL APPARATUS Application filed October 30, 1931. Serial No.572,187.

regulators of the vibratory type heretofore provided have been somewhaterratic in operation and of such construction as to be unreliable whensubjected to hard usage. These difiiculties are attributable to variouscauses among which is the tendency of certain of the parts, such as thecore, to expand when heated to such an extent as to interfere with theinitial setting and hence disturb the regulating factors.

An object of the present invention is to providea novel regulator inwhich the parts subjected to heating are so arranged that expansion orelongation thereof will have no appreciable effect on the predeterminedadjustment and setting of the device.

Another object of the invention is to provide a novel regulator which isof sturdy construction, is extremely accurate in operation and involvesa minimum number of component parts, the manufacture and assembly ofwhich may be effected without entailing any excessive expense.

A further object of the invention is to provide a regulator of the typeembodying a swinging armature which is so arranged and controlled thatthe pivotal axis for the armature remains in a fixed predeterminedposition regardless of the setting.

A further object of the invention is to provide a regulator embodying asolenoid of the fixed core type, which is so constructed that anyvariations in the length of the core resulting from absorption of heatwill have no effect upon the accuracy of the regulation obtained.

Another object of the invention is to provide novel means for yieldablysupporting the solenoid core and maintainmg it in position without theuse of any rigid fastemng means.

Another object of the invention is to provide novel means of simpleconstruction for adjusting the setting of the vibrating armature.

These and other objects and features of theinvention will becomeapparent upon consideration of the following detailed description, andupon reference to the accompanying drawings illustrating the preferredembodiment of the invention. It is to be expressly understood, however,that the drawings are illustrative only, and are not intended as adefinition of the limits of the invention, reference being had to theappended claims for such a definition.

In the drawings,

Fig. 1' is a view in elevation with parts in section of the deviceembodying the invention;

Fig. 2 is a plan view of the device with parts in section along the line22 of Fig. 1;

Fig. 3 is a view in elevation taken at right angles to the viewpoint ofFig. 1;

Fig. 4 is a vertical section view taken along the line 4 4: of Fig. 3;

Fig. 5 is a view in elevation of a second embodiment of the invention;and

Fig. 6 is a view taken at right angles to the viewpoint of Fig. 5. I

Referring to the drawings, it will be seen that the invention isembodied in a mechanism adapted to be mounted as a unit on a suitablepanel (not shown) by means of a substantially rectangular frame 5 whichis preferably of ferrous material and which is of solid construction onone side only, the other sides having openings for the positioning ofthe various parts to be described. The frame 5 is adapted to receive anelectromagnet 7 constituted by the usual coil of relatively lowresistance wire wound on a sleeve 8 tightly fitting about the core 9.Near the upper end of core 9 there is provided a portion of largerdiameter, forming a flange 10 adapted to rest on the apertured disc 11,which in turn rests on the insulating disc 12. Thus the core 9 isimmovable relatively to the coil 7 and any movement of either in anupward direction is prevented by engagement of the flange 10 with thetransversely disposed. member 13, the latter being secured to the frameby through pins 14. Mounted above the member 13 is an armature 15 hav-.armature 15 may swing in response to the mechanical and magnetic forcesexerted thereupon in opposite directions.

The armature is provided with a counterbalance 22 in order to bring thecenter of gravity of said armature to the line passing through theknife-edge 18. Extending .through the counter-balance 22 is an anchormember 23 which, as shown, consists of an enlargement on thestraightened end of a coil spring 24, the opposite end of which ishooked into an appropriate opening (Fig. 3) in a lever 25 pivotallysecured in a boss 26 held in the frame 6 by provision of the set screw27 (Fig. 1). The tension of spring 24 may be varied to modify themovement of armature 15 by means of the adjusting screw 28 on which isthreadedly mounted a nut 29 adapted to bear against the rounded end 30of the angle-piece 31 which is integral with or otherwise may be aifixedto the lever 25.

The inner end of the screw 28 is adapted to be supported and held inposition by means 33 and the vertically disposed bracket member 34, asshown best in Fig. 3. Interposed between the outer bracket 34 and theknurled head 35 of the screw is a flexible bowed disc 36 which throughits resiliency acts to maintain firm contact between the nut 29 and thelever end 30. Turning of the nut 29 with the screw 28 is prevented bythe provision of a guide block 37 riveted or otherwise secured to theframe 6 as indicated at 38, the said guide block presenting its upper'surface in the path of the nut 29 and thus restricting the said nut tonon-rotary movement along the threads of the screw 28, when it isdesired to adjust tension of spring 24. A set screw 39 serves to holdthe counterbalance in the adjusted position.

The contact 16 normally engages a stationary contact 45 carried-by theend of a screw 46 which extends through and is in threaded engagementwith an arm 47 extending from the rear surface of the frame 5 to whichit is secured b suitable means 48 (Fig. 3). As shown, t e contact 45 isinsulated by the provision of insulating strips 50 and 51.

When the electrical output of the generator or current supply means (notshown) exceeds the desired amount, which amount is predetermined inaccordance with the adj ustment of spring 24, a sufiiciently strongmagnetic field is set up by the solenoid 7 to draw the free end ofarmature 15 downwardly whereby the circuit through contacts 16 and .45is broken. The opening of the circuit may serve to place a resistance,not shown, in circuit with the field windings of the generator or otherunit whose electrical output is to be controlled. The resulting decreasein the strength of the magnetic field of the solenoid, permits spring 24to again close contacts 16 and 45. As will be understood by thoseskilled in the art, the swinging movement of the armature 15 is a rapid,vibratory one.

The novel means for yieldably supporting the core 9 and at the same timepermitting its elongation in a downward direction in response toabsorption of heat, without producing any material elongation in adirection which would interfere with the regulating action, preferablycomprises the provision of a flat spring 53 having a normally boweddisposition, as shown in Figs. 1 and 4, and operatively engaging a disc55 fixed to the core 9 as indicated at 54, the spring being flexed so asto normally bear against the lower surface of disc 55. The spring thusconstitutes a resilient support for the core 9 and permits, inconjunction with the aperture 56 in the base 6 of the frame, a downwardelongation of the core 9 in response to absorption of heat therein, anexpansion in the upward direction being prevented by the engagement ofthe flange 10 with the transverse member 13. On a rise in tem rature,the core 9 will of course elongate at oth its ends, but the elongationabove the flange 10 will be negli 'ble since the portion above theflange 1O isliut a very small fraction of the length below the flange.

Thus it is apparent'that the expansion in a downward direction cannot besuflicient to interfere with the regulating'action of the armature, asin the case of constructions wherein the core is fixed at its lower endor otherwise disposed so as to cause all the elongation to occur at thearmature end.

The embodiment shown in Fi 5 and 6 differs from that of Figs. 1 to 4lnclusive in including means for obtaining a finer ad ustment of thetension on spring 24, such means comprising a fine toothed sector 60pivoted to the support by suitable means 61 having a second pivot means62 for attachment to the end of the spring 24. The teeth of the sector60 are in mesh with the threads of the adjusting screw 28 and areoperative to vary the tension on the spring in response torotation ofthe screw by manipulation of the head 63. The construction shown in thisembodiment also differs from ,the preferred embodiment in the manner ofpivoting the armature 15. In place of the fulcrum 18 (Fig. 1), thisembodiment employs a pin 65 passing through and having its bearing intheapertured upper ends 66 and 67 of the frame, the armature 15 beingsuspended from the pin by the provision of suitable bearings 68 and 69,to which bearings is secured a U-shaped member 70, the horizontalportion of which is aflixed to the armature.

Various other changes may be made in the arrangement and construction ofthe apparatus in ways which will occur to those skilled in the art onexamination of the foregoing specification, and such changes as arewithin the limits of the invention herein disclosed are to be consideredas embraced in the appended claims.

I claim:

1. Means for regulating changes in the overall length of a solenoid corecomprising a flange on said core near one end thereof, a framesurrounding said solenoid, said frame including a transversely disposedplate apertured to receive one end of said core, and resilient meansengaging said core near the other end thereof and acting to urge saidflange into engagement with said plate, said resilient means also actingto yieldably support the solenoid.

2. In apparatus of the class described, an electro-magnet, an armatureactuated thereby, said armature being normally held in' predeterminedspaced relation to the .core of said electro-magnet, and means"including a transversely disposed plate apertured to receive thearmature end of said core for preventing any appreciable heat responsiveelongation of said core in a direction approaching said armature, saidcore being free to expand independently of said transversely disposedplate.

,3. In apparatus of the class described, an electro-magnet, an armatureactuated thereby, said armature being norm ally held in predeterminedspaced relation to the core of said electro-magnet, and means forpreventing any appreciable heat responsive elongation of said core in adirection approaching said armature, said means comprising a resilientmember engaging said core near its end remote from said armature.

4. In a device of the class described, a solenoid, a substantiallyrectangular support for said solenoid, an armature pivotally mounted onsaid support and adapted to be attracted toward the core of saidsolenoid in response to energization of the latter, and means interposedbetween said solenoid and said support for preventing any appreciableheat responsive elongation of said core in a direction approaching saidarmature.

5. In a device of the class described, a

solenoid, a substantially rectangular support for said solenoid, anarmature pivotally mounted on said support and adapted to be attractedtoward the core of said solenoid in response to energization of thelatter, and means interposed between said solenoid and said support forpreventing any appreciable heat responsive elongation of said core in adirection approaching said armature, said means comprising a resilientmember engaging said core near the end remote from said armature, saidmember also engaging said solenoid.

6. In apparatus of the class described, an electro-magnet, an armatureactuated thereby, means normally maintaining said armature inpredetermined spaced relation to said electro-magnet, and means forpreventing any appreciable variation in said spaced relation except thatproduced by the magnetic field resulting from energization of saidelectro-magnet, said means comprising a relatively stationary memberengaging the core of said electro-magnet and thus preventing anyappreciable elongation thereof in a direction approaching said armature,and means for supporting said core near its opposite end, saidsupporting means being capable of movement in response to thermalexpansion of said core at said latter end.

7. In apparatus of the class described, an electro-magnet, an armatureactuated thereby, means normally maintaining said armature inpredetermined spaced relation to said electro-magnet, and means forpreventing any appreciable variation in said spaced relation except thatproduced by the magnetic field resulting from energization of saidelectro-magnet, said means comprising a relatively stationary memberengaging the core of said electro-magnet and thus preventing anyappreciable elongation thereof in a direction approaching said armature,and resilient means engaging said core near the other end thereof, saidresilient meansalso acting to yieldably support the electro-magnet.

8. In apparatus of the class described, an electro-magnet, asubstantially rectangular member having vertically disposed sidesenclosing said electro-magnet and a base extending beneath saidelectro-magnet in a plane spaced from the plane of the base of theelectro-magnet, means extending from said vertically disposed sides intoengagement with a part of said electro-magnet to restrain heatresponsive expansion thereof in an upward direction, and meansinterposed between said base and said electro-magnet for determining thedirection of heat responsive expansion.

9. In apparatus of the class described, an electro-magnet, asubstantially rectangular member having vertically disposed sidesenclosing said electro-magnet and a base extending beneath saidelectro-magnet in a plane spaced from the plane of the base of theelectro-magnet, means extending from said vertically disposed sides intoengagement with apart of said electro-magnet to restrain heat responsiveexpansion thereof in an upward direction, and means interposedbetweensaid base and said electro-magnet 10. In apparatus of the classdescribed, an electro-magnet, an' armature actuated thereby, saidarmature being normally held in predetermined spaced relation to thecore of said electro-magnet, a tension spring having operativeconnection with said armature for maintaining said spaced relation, andmeans for varying the tension in said spring comprising a member pivotednear one edge thereof and connected to the end of said spring remotefrom said armature, a stop normally maintaining said pivoted member inpredetermined position, and means for moving said stop transversely ofsaid spring to oscillate said pivoted member and thereby vary theeffective length of said spring.

11. In apparatus of the class described, an electro-magnet, an armatureactuated thereby, said armature being normally held in predeterminedspaced relation to the core of said electro-magnet, and means formaintaining said spaced relation, said means comprising a tension springhaving operative connection with said armature, a pivoted memberconnected to the end of said spring remote from said armature, athreaded nut normally maintaining said pivoted member in predeterminedposition, and a transversely disposed screw engageable with said nut tooscillate said pivoted member and thereby vary the effective length ofsaid spring. I

12. In apparatus of the class described, an elect'ro-magnet,an armatureactuatedthereby, said armature being normally held in predeterminedspaced relation to the core of said electromagnet, and means formaintaining said spaced relation, said means comprising a tension springhaving operative connection with said armature, a pivoted memberconnected to the end of said spring remote from said armature, athreaded nut normally maintaining said pivoted member in predeterminedposition, a transversely disposed screw engageable with said nut tooscillate said pivoted member and thereby vary the effective length ofsaid spring, and bearing means for said pivoted member connected to thesupporting frame of said electro-magnet.

- 13. In apparatus of the class described, an electro-magnet, anarmature actuated there by, said armature being normally held inpredetermined spaced relation to the core of said electro-magnet, andmeans for maintaining said spaced relation, said means comprising atension spring having operative connection with said armature, a toothedsector connected to the end of said spring remote from said armature, astop normally maintaining said toothed sector in predetermined position,and means for moving said stop laterall to oscillate said toothed sectorand there y vary the effective length of said spring.

14. In apparatus of the class described, an electro-magnet, an armatureactuated thereby, said armature being normally held in predeterminedspaced relation to the core of said electro-ma net, and means formaintaining said spaced relation, said means comprising a tension springhaving operative connection with said armature, a toothed sectorconnected to the end of said spring remote from said armature, a screwnormally maintaining said toothed sector in predetermined position,means for turning said screw about an axis transverse to the axis ofsaid core to oscillate said toothed sector and thereby vary theeffective length of said spring.

15. In apparatus of the class described, an electro-magnet, an armatureactuated thereby, said armature being normlly held in predeterminedspaced relation to the core of said electro-magnet, and means formaintaining said spaced relation, said means comprising a tension springhaving operative connection with said armature, a toothed sectionconnected to the end of said spring remote from said armature, a screwnormally maintaining said toothed sector in predetermined position,means for turning said screw about an axis transverse to the axis ofsaid core to oscillate said toothed sector and thereby vary the effective len th of said spring, and means connected to t e supportingframe of said electro-magnet to provide a bearing for said toothedsector.

In testimony whereof I-have signed this specification.

JOSEPH WILLIAM ALLEN.

